System for pumping oil-wells.



PATENTED JAN. 9, 1906.

R. J. HOFFMAN.

SYSTEM FOR PUMPING OILWELLS.

APPLICATION FILED APR.17, 1905.

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No. 809,805. PATENTED JAN. 9, 1906. R. J. HOFFMAN.

SYSTEM FOR PUMPING OIL WELLS.

APPLICATION FILED APB-.17. 1905.

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ROSS J. HOFFMAN, OF BRADFORD, PENNSYLVANIA, ASSIGNOR TO HOFF- MAN MANUFACTURING COMPANY, OF BRADFORD, PENNSYLVANIA.

SYSTEM FOR PUMPING OIL-WELLS.

Specification of Letters Patent.

Patented Jan. 9, 1906.

Application filed April 17, 1905. Serial No. 256,147.

1'0 (ML III/1 0721 2'25 Uta II concern:

Be it known that 1, Ross J. HOFFMAN, a citizen of the United States, residing at Bradford,

Pennsylvania, have invented certain new and useful improvements in Systems for Pumping Oil-Wells, of which the following is a specification.

My invention relates to a system of pumping oil-wells and controlling the flow of oil through the system, and it includes among its features a central power plant, connected by pipe-lines to pumps located at different parts of the field, which pumps are capable of adjustment as to power of delivery according to the capacity of their respective wells and are adapted to be operated on both strokes positively, so that the delivery from each well may be accurately gaged, in order that all the wells of one groupi. e., those which are connected on the same supply-main-will be exhausted at the same time irrespective of their relative capacities, thereby rendering it possible to control a group or series of wells by means of a single throttle-valve connected with the main which supplies the said group or series, all the pumps being started simultaneously and all exhausting the wells at the same time.

In carrying out my invention I employ pumps located at the different wells and operated by compressed air derived from the central power-station and for the purpose of insuring the proper flow of oil through the delivery-pipes and also for cleaning out the said pipe, when required, either of the oil or of any accumulation or substance which interferes with the proper delivery of the oil I connect the delivery-pipes at points close to the wells with the compressed-air supply, so that from the point at which the oil enters the system to the delivery point it may be subjected to the force of the compressed air, which will drive it out to the receiving-tank, aiding the pumps when the system is in operation, or, when the pumps have stopped, serving to clear the pipes of oil or other substance contained therein, thus leaving them empty and preventing freezing or clogging.

The invention consists in the features and combination and arrangement of parts hereinafter described, and particularly pointed out in the claims.

In the drawings, Figure 1 is a diagrammatic view of anoil-producing system as connected up in the oil-field. Fig. 2 is a side view of a pump in the position assumed by it when connected with the well and having, the compressed-air pipe connected thereto, and Fig. 3 is a front view of the said pump. Fig. i is a view of the compressed-air valve.

In the drawings, 1 indicates the powerhouse, having therein the air-compressor 2, which delivers compressed air to a reservoir or after cooler 3, and from this reservoir pipes A, 5, and 6 are shown as leading off to different parts of the field, these pipes being representative of any suitable number or arrangement of pipes which may be used in reaching different portions of the system. From each of these main air-pipes branches lead off to the different wells, which are indicated by the circles-for instance, at a, b, 0, (Z, c, f, and which circles also answer as representative of the oil-pumps located immediately over the wells and directly connected with the standpipes leading up from the wells. The diagram also illustrates lead-pipes a 1/0 CZ e f g, into which the oil from the several pumps above mentioned is delivered to be conveyed thereby to a central tank A. The pumps (6, Z), c, 850., above mentioned, belong, to one group, as they are all supplied with compressed air from the one main, (shown at at.) There may be any number of groups of wells connected up in this manner, and I have shown another group connected with the main 5 and a third group connected with the main 6.

The pumps which I employ are similar in construction and operation to that disclosed in Letters Patent of the United States, No. 773,501, granted October 25, 1904, to myself and E. H. Hollingshead, said pump being adapted for direct attachment to the stand pipe and arranged axially in relation thereto, and being also adapted to be operated positively on both upward and downward stroke by the pressure of air and, further, having means whereby the said pump may be adjusted as to its delivery, so that in a group of wells where the said wells vary in capacity the pumps belonging to the said wells may be adjusted as to their delivery power according to the capacity of their respective wells. In this way the whole group of wells may be controlled by a single throttlevalve,such as shown at 7, connected with the main compressed-air supply-pipe 4:. By having a pump which is driven positively in both directions or on both strokes by the compressed air and capable of regulation as to its delivery it will be seen that all the wells of the same group or series may be exhausted simultaneously notwithstanding the fact that they are of relatively diflerent capacities, for by adjusting the several pumps to correspond to the capacity of their respective wells all of the wells may be exhausted at the same time, and by reason of this a single throttle-valve may be used to control the whole group.

As is well known to those skilled in the art, it is difficult in cold weather to keep the leadlines from freezing, because more or less water or moisture is mixed with the oil and after the wells have been pumped some oil is left standing in the lead-lines, and this often freezes, resulting in clogging of the pipe if not in rupturing the same. In order to overcome this difficulty and to secure other advantages hereinafter named, I provide for introducing compressed air into the diflerent lead-lines at a point as close as possible to the point of entrance of oil from the pump into the lead-line, and for this purpose I arrange a branch pipe, as at 8, extending from the compressed-air main or from the branch which leads therefrom to the pump, the saidbranch 8 connecting with the lead-line at or near the point of entrance of the oil into said lead-line. This branch 8 may be controlled by a stopcock 15, and this is preferably employed in the form of a rotary plug in a suitable casing and having an aperture extending therethrough for the passage of compressed air. When this valve is fully open, the compressed air will enter the lead-lines and will assist in forcing oil therethrough, and when the oil is all pumped from the well and the pump itself is out of operation the compressed air maybe employed to entirely clear the lead-lines of oil and to force the said oil into the tank, and in this way there will be no danger of freezing of the fluid in the lead-line, as now often occurs, as when the pumping has been completed the system may be left entirely free from oil or other fluid mingling therewith. Further, the compressed air when the system is in operation will assist in forcing the oil, especially where the lines run up hill, and thus back pressure on the oil-well pump will be relieved. The air is introduced into the lead-lines at about a pressure of forty pounds to the square inch, and as it leaves the inlet-orifice and enters the lead-line the rapid expansion of the air produces a reduction in the temperature, which results in condensing any gases in the lead-lines which are delivered thereto from the pump, and the oil of condensation recovered in this manner is delivered into the tank with the main body of oil and adds materially to the yield from the well. The stop-cock 15 is provided with a small opening 16 for the passage of the proper amount of compressed air for condensing the'gases; but when the pipes are to be cleared-the cock is opened all the way. I employ check-valves, such as shown at 9, in the lead-lines at the point ofjunction of the said lead-lines in order to prevent the compressed air when let into one arranged to close toward their respectivepumps, or, in other words, toward the pumps which force the oil through the particular one of the pipes in which said check-valve is located.

It will be understood that the supply of compressed air to the pump-cylinders takes place through the branch pipe 10, controlled by a throttle-valve at 11, and the piston of each pump is operated positively in both directions by the compressed air, this beingintroduced through the pipe 12, first into one end and then the other end of the cylinder. Each pump is adjusted as to its delivery or the amount of oil to be drawn from its respective well by increasing or decreasing the number of strokes of the piston per minute by adjusting the throttlevalve at 11' until the proper number of strokes per minute is obtained on each respective Well to cause them all to be pumped off at the same time.

It is essential to the operation of my improved system that the pumps be operated positively in both directions; otherwise it will be impossible to control a group of pumps from a single throttle-valve, for obviously if the action of any pump becomes irregular or varies in the volume of its delivery from that determined upon the'well belonging to this pump will not be pumped ofi simultaneously with the other wells, and thus one object of my present invention will be defeated; but if each pump is adjusted as to the volume of its delivery to correspond with the capacity of its well and then all the pumps of the system are so operated that each has its required number of strokes to pump it'ofi in a given time, which is the given time that all theother wells in the group require in which to be pumped ofiZ the pumping off of the entire group of wells will occur simultaneously, and the whole group may be controlled by a single throttle-valve, as described.-

I do not claim herein the method disclosed in the above description, as this has been made the subject-matter of-another application filed by me April 17, 1905, Serial No. 256,148:

I claim as my invention 1. A system of pumping oil-Wells consisting of a plurality of pumps, a pipe or main for conveying compressed air, branches leading.

therefrom to the several pumps, lead-lines for conveying oil from the several pumps, connections between the said lead-lines and the compressed-air supply-pipe for introducing compressed air into the lead-lines, substantially as described.

2. A system of pumping oil-wells consisting of a plurality of pumps, means for supplying compressed air, branches leading therefrom to the several pumps, lead-lines for conveying oil from the several pumps, connections between the said lead-lines and the compressedair pipes for introducing air into the lead-lines and a single valve for controlling the compressed-air supply to the several pumps, substantially as described.

3. In combination, in an oil-Well system, a plurality of pumps, lead-lines for conveying the oil from the said pumps, said lead-lines being in connection with each other to convey the oil to one delivery-point, means for introducing compressed air into the lead-lines, and check-valves in the lead-lines to prevent back pressure, substantially as described.

4. A system of pumping a plurality of oilwells comprising a pump for each Well driven positively on both strokes and having means for adjusting the action of each pump to the capacity of its well in relation to the capacity of the other wells, a source of power for operating the pumps, pipe-lines extending from the source of power to the pumps and a single controllingvalve to control the supply of power to all the pumps whereby wells of varying capacity may be pumped ofi in the same period of time and the pumps started or stopped by the manipulation of a single controlling-valve.

5. In a system of pumping oil-wells, the lead-lines. compressed-air pipes and a valve having a large and small passage therethrough, said small opening being adapted in size to admit sufficient air for liquefying the gas and the large opening admitting enough air to clear the oil-delivery pipe, substantially as described.

In testimony whereof I afiix my signature in presence of two witnesses.

ROSS J. HOFFMAN.

WVitnesses:

EDWIN E. TAIT, KATHARINE BURKE. 

